Electric refrigerating apparatus



Jan. 22,1929. 1,699,564

c M. DAVlSON ELECTRIC REFRIGERATING APPARATUS orisinal Filed ne 12. 1926 2 Sheets-Sheet 1 gmnnto'o Jam 22, 1929..

2 Sheets-Sheet 2 Patented data 223, 1329..

urnran s'rarss earner .orrlcs.

CLARENCE ZVZ. DAVISOYN', F BALTIMORE,

MARYLAND, ASSIGNOR TO POOLE ENGINEER- ENG: All?) MAGHINE GOMANY,, @F BALTIMQRE, MARYLAND, A CORPORATION OF mananaun.

ELECTRIC REFRIGERACEING APPARATUS.

driginal application filed Zl'une'w, 1926, Serial No. 115,532

Illivided and this application filed January 15,

192?. Serial lilo. 161,323.

This invention relates to refrigerating apparatus and particularly to that type of apparatus known as electric refrigerating apparatus primarily adapted for household uses. While the present invention is shown embodied in an apparatus or system of that type, there are, however, certain features which may be utilized in refrigerating systems difi erent from the s ecific form shown.

Primarily, the object o? the present invention might be generally stated as consisting in an efi'ort to increase the eficiency of the apparatus or system without adversely affecting its cost of production and operation to any appreciable extent,

More specifically, one object of the invention isto provide a cooling element or unit so constructed that after the refrigerating chambers thereof have been reduced to the desired temperature and the circulating ofthe cooling unit discontinued, the lowered tempera tures existing within the chambers of said unit will be maintained for a considerableperiod of time without the necessity of re establishing the circulation of a refiigerat ing medium to said unit. This is preferably accomplished by having the cooling unit provided in its interior with a mass of material of high thermo-capacity and relatively low thermo-conductivity. During the circulation of the refrigerating medium through the cooling unit the temperature of this mass of material is reduced as is also the temperature within the cooling chambers of said unit, and by reason of the fact that said mass of material will absorb heat units from the cooling chambers or the articles sought to be preserved in said cooling chambers, it necessarily follows that after the circulation of the f refrigerating medium has ceased a comparatively low temperature will be maintained for uite a period of time within the cooling 0 ambers by said mass of material. With the cooling unit formed with such a mass of ma terial of high thermo-capacity d of relativel low thermo-conductivity,1f a door ofthe-refrigerator should be opened, after the circulation of the refrigerating medium has.

ceased, the relatively hot air would thus be admitted to the cooling chambers and would not necessitate the immediate operation of the fluid circulating mechanisms for purposes of compensating for the decrease of temperature within said chambers as the heat units thus admitted to said chambers would be com- 5 pcnsated for to a very large extent by reason of the presence of the mass of material of high thermo-capacit 1 Another object contemplated in the present instance is the reduction of the quantity of a refrigerating medium or chemical that must be circulated through the cooling element or unit. This reduction of "chemical is accomplished in the present instance by having the circulating passages for said chemical in the cooling unit made of comparatively small cross sectional dimensions so that when the chemical is introduced therein under reduced. pressure ebullition and gasification thereof Wlll take place with such rapidity and vidlence that it is only necessary to partially fill the passages with the liquid chemical due tothe fact that this violent ebullition causes the passages for the chemical to be entirely and completely filled with the liquid chemical m xed with the resulting chemical gas.

in the accompanying drawings: a Figure 1 is a more or less diagrainmatical illustrationof an electric refrigerating sys- Fig. 2 is a front end view, partly in section, showing the cooling unit in more or less detail.

Fig. 3 is a longitudinal sectional view of said unit. While features contemplated by the present invention are not limited to use in any particular design of refrigerating system there is shown in the present instance a system in, which such features have been used with very" satisfactory results. 7 V

In the system .illustrated there is a compressor A driven by a motor B for compressing and circulating the refrigerating chemical through the system. The refrigerating chemical in gaseous form passes from the casing of compressor A through a pipe 20 to a condenser C where it is liquefied and from thence it flows by a pipe 21 to the cooling element or unit E Where it is gasified upon takng up the heat units present in said cooling 100 element. The chemical thus gasified in the cooling unit flows through pipes 22 to a drum F and from said drum it is returned by a pipe 22 to the compressor A where it is agaln placed under pressure and circulated through 105 the system as just described.

e compressor A comprises a pump which may be of any desired construction and as the present invention resides in the cooling unit of the system illustrated, no detailed description of said compressor or its pump is deemed necessary in the present instance. The same is true of the condenser C which is shown in the present instance simply in the nature of a coil. In this connection it should be stated that the present application, which, as just mentioned, is confined to the cooling unit of the system, is a division of the prior application filed by the present applicant, Serial No. 115,532 filed June 12, 1926. In said prior application the compressor A and the condenser C are both fully shown and described.

The refrigerating chemical, in liquid form, flows through provided in the cooling element for the purpose of extracting the heat units from the chambers in said element in which articles or commodities to be refrigerated are located.

In the preferredconstruction of this cooling element there is an outer casing 24: within which there is a container 25 preferably cylindrical, a relatively narrow chemical circulating passage 26 being provided between said casing and container to which the chemical is supplied by a pipe 21 at the bottom thereof. The container 25 is composed of a masso material of high thermo-capacity and low thermo-conductivity such as cast iron or steel and glass or porcelain formed with cavities therein in which are located the metallic shells 28 forming the compartments for receiving the trays or other holders for the articles to be refrigerated. For bringing the chemical into intimate contact with the walls of the shells 28 there is a fluid circulating passage 29 which extends around each of the shells as well as between said shells. The shells 28, container 25 and casing 24 are held in proper spaced relation by suitable studs 32 formed on said container. The chemical has access to these passages 29 around and between the shells 28 by way of ports 30 provided at longitudinally spaced points in the bottom and top of the mass constituting con-' tainer 25, and elongated passages 31 extending practically the entire length of the container 25 and connecting the ports 30 with the passages 29.

Preferably the shells 28 are arranged as shown so that as the chemical passes around the sides of the lowermost shell it will impinge against the bottoms of the two next uppermost shells and the latter will act as bafiies to cause the current of chemical to be broken up, portions of the chemical being diverted around opposite sides of the said next uppermost shells. Likewise, as the chemical flowing between the two intermediate shells comes into contact with the uppermost shell of the group, it will also be broken up or part of said current diverted around one side of the uppermost shell and part around'the opposite side of said shell, the entire volume of pipe 21 into suitable passages chemical ultimately passing through the upper passages 31 and ports 30 into the upper passage 26 from which it will flow to the pipes 27 into the gas drum F located above the cooling element. From the drum F the chemical in its gasified state is returned by pipe 33 to the port through which it is admitted to the pump of compressor A.

In order to reduce the quantity of chemical necessary to effect the proper exchange of heat units in the cooling elements the passages 26 and 29 are made of very narrow cross section so that when theliquid chemical is released into the side passages in the cooling unit under a reduced pressure violent ebullition and gasification of the chemical will result, the expanded chemical completely filling the entire passages above the static level which the liquid may assume when it is not being circulated in said passages.

With some types of refrigerating systems it has been found that after the temperature in the cooling unit has been reduced to the desired point and the system has been temporarily rendered inoperative so far as the continuation of the circulation of the refrigerat ing medium is concerned, said unit is so sensif tive that if a door of the cabinet in which it is.

contained is'opened said cooling unit is affected to such an extent that the system must be again immediately placed in operation if the desired reduced temperature is to be maintained in said unit. In the present in: stance, however, this instantaneous renewal of operation of the system is eliminated by the provision of the mass of material 25 of high thermo-ca acity and of low thermo-conductivity in t e cooling unit. When the present system is in operation the temperature within the interior of ,shells 28 as w'ell as the temperature of this mass, which is preferably of cast iron, is reduced to the desired degree whereupon the system is rendered in- I operative so far 'as the circulation of the refrigerating medium is concerned and if the door of the cabinet should be opened and relatively hot air admitted the heat units carried by such air will be absorbed by the mass of the container 25. That is, there will be an exchange of heat units between the relatively hot air and the mass 25 due to the relatively low thermo-conductivity in said mass and little, if any, efiect will be had upon the'interiors of the shells 28. The cast iron being of high thermo-capacity a large volume of m heat units may thus be taken up by it before it is again necessary for the system to resume operation. For convenience in manu-, facture and assembly this mass 0t iron. is cast in two semi-circular sections which can be readily inserted in the container 25.

What I claim is:

1. In a cooling unit for refrigerating systems, a container having a group of cavities therein for receptacles containing articles to my be chilled, and refrigerant medium conducting passages surrounding said group of cavitles, the opposite walls of the respective passages being in close proximity to each other to form comparatively narrow passages whereby violent ebullition and gasification of a gi1antity of liquid refrigerant medium only su cient to partially fill said passages will resultin the entire passages being filled with the expanded medium, said cavities being arranged in staggered relation whereby suc- 7 the cessive receptacles will act as baifies in the path of refrigerating medium circulated through said passages to-deflect portions of medium in different directions; v 2. In a cooling unit for refrigerating systems, a container, a plurality of cavities in said container for articles to be chilled, said container having a passage in its wall for a refrigerating medium and there being addi tional the container wall but adjacent and surrounding said cavities, and means of high thermocapacity and low conductivity interposed between the two passages and surrounding the cavities, said means being capable of having its temperature lowered by the refrigerating medium whereby the lowered temperature capacity and low conductivit within the cavities may be partially maintained after circulation of the refrigerating medium has ceased.

3. In a cooling unit for refrigerating systems, a container having a series of cavities therein forthe articles to be chilled and refrigerating medium conducting passages surrounding said cavities, and means of highthermo-capacity and low conductivity surthe rerigerating medium, whereby heat units may be absorbed by said means after circulation of the refrigerating medium has ceased.

4. In a cooling unit for refrigerating systems, a mass of material of high thermothere being rounding said cavitiesand passggrgsp adapted to have its temperature lowere cavities within said mass for receptacles conpassages for said medium spaced from and low conductivity having ports t thermo-conductivity for malntaining the reduced temperature within said shells afterthe circulation of the refrigerating medium has ceased.

6. In a cooling unit for refrigerating systems, a series of hollow shells for articles to be refrigerated, said shells having passages on their exterior for circulating a refrigerating medium around their exteriors to reduce the temperature therein, and a mass of metal of low thermo-conductivity for maintaining the reduced-temperature within the shells after the circulation of the refrigerating medium has'ceased.

7. In a cooling unit for refrigerating systems, a container, a mass of hi gh thermocapacity and low thermo-condu'ctivity within said container and having its surface spaced from the container, there being a series of cavities within said mass in which articles to be refrigerated may be deposited and there being passages between said'mass and said cavities for circulating said refrigeratin medium around the" exterior walls of sai cavities, said mass of'high theme-capacity erein connecting thespassages around said cavities with the space between said mass and container.

CLARENCE M. DAVISON.

' ing medium around their exteriors to reduce the temperature therein, and means of' low 

